A 1964 study of correctional officer selection and a 1971 study of police officer selection showed an inordinate reliance on written tests to determine capability. At the same time, private industry relied mostly on interviews for human contact positions along with an emphasis on references and ratings. Results of the 1979 survey are somewhat different. In this survey, which contacted major city police departments, correctional institutions, and private corporations of name-brand calibre, results show that police still emphasize written testing over interviews, but corrections have reduced their emphasis on testing in favor of interviews and have arrived at about equal use of each. Private industry generally has increased its reliance on tests although it still uses interviews predominantly. Private security emphasizes references and interviews and uses very little testing in selecting personnel. Three notes are included. (Author abstract modified)